Tuesday, 1 November 2016

First of all, a slightly late happy Halloween to you all! I wanted to post something about a slightly spooky creature to celebrate this time of year, but the organism that I have chosen isn't a spider, or a vampire bat, or an equally well-known scary critter, but a fungus known as Cordyceps. This little ascomycete (sac fungus) may be small and seemingly unassuming, but through millions of years of evolution it has mastered the art of mind control. One of the best known species is Ophiocordyceps unilateralis. This parasitic fungus has made one species of ant its unwilling servant, thanks to a very clever trick of evolution, which some suggest may have been around for 48 million years or more.

The story begins with a Camponotus leonardi ant or one of its close relatives. It will be wandering around, minding its own business and working hard to keep its colony alive and well, when it will become infected - the spores of O. unilateralis will become attached to its body. They will stick to the hard carapace of the insect, but bit by bit, using enzymes and pressure, they will break through the exoskeleton and make it into the ant's body. This is when things start going really wrong for the insect. The fungus starts releasing compounds into the ant's body that affect its behaviour. The first signs are sudden convulsions, causing the ant to fall to the ground, only to recover, seeminly non the worse for ware. But underneath its exoskeleton, the fungus has the ant under its control. Suddenly the ant will begin climbing up nearby vegetation, at the command of the fungus, until it comes to a leaf, where it will bite down hard with its mandibles. The fungus will begin to work away at the insect's jaw muscles, destroying them so that the mandibles cannot be moved: the ant is trapped, biting down onto the leaf and unable to let go and escape. But now the ant has done its bit, it's got the fungus off the forest floor, now it is disposable. The fungus kills it, leaving it hanging there even in death, and the corpse will become a fortress, a sort of safe house from which the O. unilateralis will eventually be able to reproduce. The fungus will spread long, branching filaments, known as hyphae, thoughout the ant's body, fortifying the outer shell of the insect, making it safer. Mycelia - thread like structures - are sent out from the insect body to attach to the leaf, to secure it in place even further. Antimicrobials are released, protecting the corpse from microbes which would seek to break down the insect's body, which would ruin the fungus's plans completely.Once it is ready, the fruiting body of the fungus will break out of the ant's head, a single stalk bursts out of the exoskeleton and gradually grows longer, until it finally completes its life cycle by releasing its spores. Now the reason for controlling the ant's behaviour becomes clear: by leading its host to a high up leaf, then from this vantage point the fungus can release its spores, which will have more chance of spreading than if they were released on the ground. This way they can drift down onto foraging ants, infecting them too, and so the cycle continues.

2 dead ants infected with the fungus. They are biting onto the leaf and have the fruiting stage of O. unilateralis emerging from their body to spread spores.

The true story of the ant and the parasitic fungus should be thought of as an incredible example of how a little bit of evolution can achieve practically anything. So hats off to the Cordyceps fungus, for reminding us not only that whatever us humans can think up, nature's probably already done it, but also that we should never underestimate the small things in nature.

Monday, 3 October 2016

I have long been an admirer of Darren Naish, and his wonderful animal-related blog, Tetrapod Zoology, which covers topics such as paleontology, cryptozoology, speculative evolution, and general biology. He posts informative and funny pieces on . . . well, pretty much everything zoology-related. Therefore I was excited to hear about the convention that was to be coming up this year . . .In the last few years, Darren and others such as John Conway (a paleoartist who is renowned in the paleontological community) have arranged this convention at the WWT London Wetland Center. Stalls selling books, art prints, and cuddly (but scientifically accurate!) prehistoric creatures are set up, and talks on zoology are done throughout the day. I had previously only heard in passing about these events, but this year, a few days before the Tetrapod Zoology Convention (or TetZooCon for short), we heard about the event, and I did some more research. We decided, at the last minute, to buy 2 tickets for the convention - one for my mum, and one for me. We originally planned to stop over in London and make a weekend of it, but unfortunately our budget didn't allow that in the end - however, it was certainly worth getting up at 4 o'clock in the morning, enduring the rowdy group of singing, drunken teens on the train, and paying a fairly big chunk of money, to get to the event and be with like-minded people.

When we first arrived, I was a bit shy, because I was the youngest person there (the majority of people there were adults), but I quickly got into the flow of things. We had a quick look at the stalls, then watched the first talk, which was by Darren Naish, and was on the subject of sexual displays in dinosaurs, such as crests, long necks, etc. Then we moved onto a very different topic in a talk by Charles Paxton, who gave us the statistics of the Loch Ness Monster. His talk, while mostly graphs and numbers, was a very amusing and interesting piece.Next up was a talk by Jim Labisko, on the obscure frogs known as sooglossids, a native of the Seychelles. He talked about the different species of sooglossids, their mating habits, and his research into them. Afterwards, 2 preserved sooglossid specimens were passed around for us to look at.We then had a life-sized, accurately coloured Psittacosaurus model, and a talk on how it was made. Afterwards, we each got some plasticine and some bristles (for the integument on the dinosaur's tail), and sculpted our own models. My effort was pretty bad, but I decided to have fun with it, so I just made a head with a speculative wattle and bristly integument.

During a break in the talks, I had my books signed - Recreating An Age of Reptiles was signed by Mark Witton, and all Yesterdays was signed by John Conway and Darren Naish, who drew me a feathered oviraptorid and a sauropod with an inflatable neck pouch, respectively.During the lunch break, my mum and I went for a walk around the Wetland Center, as we had never been there before. I very much enjoyed seeing the variety of exotic wildfowl (including one of my favourites, the southern screamer), but the Asian short-clawed otters eluded us.

During the afternoon, we had even more great talks, on a variety of subjects, including bears, kneecaps, pterosaurs, and native reptiles and amphibians. The talk on kneecaps by John Hutchinson was very interesting indeed, and it had many pictures of the weird and wonderful variety of kneecaps, particularly in birds.Next came the talk on pterosaur reproduction by David Unwin, which was amusing and informative in equal measures. I found this talk particularly interesting, because I find it fascinating to imagine tiny pterosaurs emerging from their eggs and in relatively little time, being able to fly.Hannah O’Regan then gave a great talk on the history of bears in Britain, discussingour somewhat strange relationship with these animals, which varies from teddy bears to bear-baiting.Next upwas a talk by Angie Julian, who discussed the different species of native reptiles and amphibians, then moved onto talk about the dangers they face, and what we can do to help.

Then last but not least, we had Katrina van Grouw, who gave a brief presentation on her upcoming book, Unnatural Selection, which I'm very excited about.Then came the finale: the quiz. There were around 30 questions, and I got 18 of those right, but I could have got higher, if only I could have remembered that kune-kunes are types of pig! I was pleasantly surprised toget a prize for being the youngest to attend, and now the little model Stegosaurus baby that I got has pride-of-place on my desk.

As we had a train to catch, we didn't join everybody else in the pub afterwards, but I was extremely pleased that I went. As another TetZooCon is planned for 2017, I will most certainly try and get there, if I can!

Finally, I want to thank Darren Naish and John Conway for arranging the Tetropod Zoology Convention.

Wednesday, 28 September 2016

Hello all, this isn't really a proper update, just a little bit of news. Well, the famed blog Tetrapod Zoology hold events every so often in which biologists do talks, and books, etc are sold. Discussions on paleontology, biology, evolution, speculative evolution, and cryptozoology are held, and just as good, there's tea and coffee included in the admission price! This year it's been held at the London Wetland Center, a place that I have always wanted to go.We've decided to go, much to my excitement, that my mum and I are going to go! We should be staying in London for the Friday night, and going to the event the next day. I'm very excited, because I've always wanted to go to one of these events, and I should get the chance to talk to like-minded people, and maybe even get some of my paleontology books signed.I will make a post about the event once I've got back!

Monday, 26 September 2016

What comes to mind when someone says the word 'rainforest'? No points for saying 'rain'. Most people would imagine a steamy, tropical envioroment, lush and green, with palms and ferns growing everywhere, and monkeys and parrots frolicking in the canopy. This is the typical image of a rainforest, and it is one that I shared with most of the public up until a few years ago. Most people think that rainforests are restricted to tropical envioroments, making the words rainforest and jungle pretty much synonymous. This is actually a false image, and when you think about it, it makes sense. The definition of a rainforest is simply an area of woodland in which the annual rain level is between 250 and 450 centimetres - notice the exception of the word 'tropical'. It only makes sense that there would be 2 variations of rainforest: the tropical type, which we are used to, and the temperate type. And indeed, this is true, although many people don't realise it. The temperate rainforest habitat is just as fascinating as its tropical counterpart, but for a few years, my knowledge of it was pitiful in amount. Recently, a personal project on creating a speculative ecosystem lead me to do some more research on the habitat, and I was so fascinated by what I found, that temperate rainforest has immediately been promoted to high up on the list of my favourite habitats. I have decided to write a blog post about what I found out.

Perhaps one of the reasons that temperate rainforests are so little known is that they are not very common.

The above is a map of the distribution of tropical rainforests. As you can see, the habitat is in large chunks in South and Central America, Africa, Madagascar, and in the south-west Asian islands.

Now compare that to this:

By KarlUdo - Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=9468236

The above is the distribution of temperate rainforests. While they can be found in a variety of countries, they are in much smaller areas than in their tropical counterparts.

Perhaps the most well-known definition of a temperate rainforest is by Alaback:

"Annual precipitation over 140 cm (55 in)

Mean annual temperature is between 4 and 12 °C (39 and 54 °F)."

However, this applies only to North American temperate rainforests.In short, the habitat in general is anywhere where a forest recieves large amounts of rainfall, creating a typically damp habitat.

By Wsiegmund - Self-published work by Wsiegmund, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=336095

An image taken in the Pacific temperate rainforest ecoregion, in North America. It is the largest temperate rainforest ecoregion in the world.

This location is of special interest for being a standout example of the habitat. In certain areas, the biomass is at least4 times that of any similar area in tropical regions.

The Pacific temperate rainforests are mostly coniferous, but they do sometimes have an understory of deciduous shrubs and trees. It rains a lot during the winter, but not so much during the summer - however, during the latter season, fog creeps through the forest, letting water droplets collect on surfaces, which then drip to the ground, keeping the envioroment moist. The habitat is mostly coastal, which leads to an interesting combination of both marine and forest species - for example, salmon come in from the sea, and swim up the rivers which wind their way through the rainforest. The salmon, returning inland to spawn, attract predators, such as bears. Grizzly bears, although once more widespread in the habitat, are now mostly confined to areas north of the Canada-US border. Black bears and their beautiful white subspecies, the Kermode or spirit bear, are present here.

An unusual species found in this habitat is the marbled murrelet. This small seabird feeds mostly on sandeels, and will also feed on other small fish - but what's odd about this marine piscivore is its nesting habits. Most seabirds nest on cliffs, so that they are relatively safe from predators, and so they are beside the sea. However, the close proximity of the rainforest to the ocean has meant that the marbled murrelet has decided to take the jump to nest not on cliffs, but in the forest. It makes nests out of moss and lichen amongst the branches of conifers, sometimes up to 80 km inland!

The Appalachian temperate rainforest can be found in the southern Appalachian Mountains. There are multiple subcategories of forest that can be found within the habitat: at low elevation, mixed woodlands can be found, at middle elevation spruce is predominant, and at high elevation it is fir. The Appalachian rainforest is notable for its high diversity: around 10,000 species can be found here, including several endemic species of vertebrates. There are more than 30 salamanders that can be found here, as the damp envioroment isperfect conditions for them. Most do not have lungs, instead breathing directly through their skin.

There are also 2 species of endemic turtles. Perhaps most predominant are the fungi: there is an estimated 2000 species living here, with many more yet to be identified.

The Valdivian temperate rainforest is located in Chile, with a small part creeping into Argentina. They can easily be told apart from other temperate rainforests discussed so far by the plant life here. Angiosperms are the most predominant trees, but conifers are also present, in the form of monkey puzzles, fitzroyas, and others. Understories consisting of bamboo and ferns can also be found, home to species such as Chusquea quila, an endemic bamboo, and giant rhubarbs.

There are a variety of unusual mammals present in this habitat, including the monito del monte. This small marsupial is a nocturnal, arboreal insectivore, occaisonally feeding on fruit. Worryingly, this endearing little mammal is declining, due to deforestation and fragmentation of habitat, and predation by introduced domestic cats. The locals also kill them because they believe they are bad luck, and they think that it causes diseases and is venomous - this has led to incidents such as houses been burnt down simply because this creature was seen inside. In reality, these animals are harmless, but may soon need our help if they are to survive.

The Japanese temperate rainforest is a habitat found on Japanese islands, dominated by firs in alpine areas, and beeches and other broadleaves being predominant in areas of lower elevation. Up to 5300 species of plant can be found in this habitat, 40% of which are endemic to Japan.

Several unique creatures can be found in the Japanese temperate rainforest, such as birds like the black woodpecker, and mammals like the arboreal Japanese dormice, Japanese serow, and Japanese macaques. In the forest streams, the vulnerable Japanese giant salamander can be found.

Of course, this is just a brief look at the temperate rainforests. They are also present in New Zealand, Australia, UK, and elsewhere - but I decided to focus on the examples which were particularly unique, or simply interested me more than the others.

I think that the damp, foggy, dripping, mossy habitat of the temperate rainforest is a wonderful one - and the flora and fauna which live there are fascinating. Unfortunately, they are also threatened by habitat loss and other dangers.

I hope that you have enjoyed this look at the temperate rainforest, a unique and wonderful habitat, and have maybe been inspired to think about rainforests differently.

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Beetle Boy

About Me

My name is Jacob, and I'm 15 years old. Ever since I've been able to walk, I've been fascinated by the natural world, whether it be living or extinct. My fascination with wildlife, speculative evolution, and paleontology has gone from there, and I now hope to one day work with animals.
My hobbies include drawing, acting, writing, and imagining weird things that lived millions of years ago.